A valve timing controller includes: a driving-side rotation member synchronously rotating with respect to a crankshaft of an internal combustion engine; a driven-side rotation member disposed coaxially with a rotation axis of the driving-side rotation member, and rotating integrally with a camshaft of the engine; a phase setting mechanism setting a relative rotation phase between the driving-side and driven-side rotation members; a brushless motor driving the phase setting mechanism; a control portion controlling the brushless motor by electrifying an inverter having three sets of arm portions having high-side and low-side switching elements connected to each other in series between a first power supply line and a second power supply line connected to a potential lower than a potential of the first power supply line; and a command information acquisition section acquiring holding command information indicating a command for holding a rotor of the brushless motor in a non-rotating state.

A valve timing controller includes: a driving-side rotation member synchronously rotating with respect to a crankshaft of an internal combustion engine; a driven-side rotation member disposed coaxially with a rotation axis of the driving-side rotation member, and rotating integrally with a camshaft of the engine; a phase setting mechanism setting a relative rotation phase between the driving-side and driven-side rotation members; a brushless motor driving the phase setting mechanism; a control portion controlling the brushless motor by electrifying an inverter having three sets of arm portions having high-side and low-side switching elements connected to each other in series between a first power supply line and a second power supply line connected to a potential lower than a potential of the first power supply line; and a command information acquisition section acquiring holding command information indicating a command for holding a rotor of the brushless motor in a non-rotating state.

A system of controlling an engine provided with a dual continuously variable valve duration device may include an engine, an intake valve for selectively supplying air or a mixture of the air and fuel to the combustion chamber, an ignition switch to ignite a burner to burn the mixture, and an exhaust valve disposed in the combustion chamber to selectively discharge exhaust gas in the combustion chamber to an outside of the combustion chamber, the dual continuously variable valve duration device provided to adjust an intake duration of the intake valve and an exhaust duration of the exhaust valve, a warm-up catalytic converter including a three-way catalyst for purifying hydrocarbons, carbon monoxide, nitrogen oxides contained in the exhaust gas downstream of the engine, and a controller for adjusting an ignition timing, the intake duration and the exhaust duration of the ignition switch based on a driving condition of a vehicle.

Provided is a control device for an internal combustion engine equipped with a cam switching device including a cam groove provided on the outer peripheral surface of a camshaft and an electromagnetic solenoid type actuator capable of protruding, toward the camshaft, an engagement pin that is engageable with the cam groove. The control device is configured, in causing the cam switching device to perform a cam switching operation, to perform energization of the actuator such that the engagement pin is seated on a forward outer peripheral surface, and to more lower, when an electric current (coil current) flowing through the actuator as a result of the energization is greater, an average electric voltage per unit time applied to the actuator in protruding the engagement pin toward the cam groove from the forward outer peripheral surface.

An electronic control unit of a control device for an internal combustion engine executes, for a first cycle, first drive processing for controlling an actuator such that a pin drive operation is executed for switching from a first cam to a second cam, executes second drive processing for controlling the actuator such that the pin drive operation is executed again for a second cycle, and executes abnormality determination processing for determining that a cam switching mechanism has an abnormality in a case where a pin returns to a reference position by using a pin return section following a cam switching section of the first cycle after the execution of the first drive processing and the pin returns to the reference position by using the pin return section following the cam switching section of the second cycle after the execution of the second drive processing.

An internal combustion engine system is provided with a cam switching device including a cam groove provided on the outer peripheral surface or a camshaft and an actuator capable of protruding, toward the camshaft, an engagement pin that is engageable with the cam groove. The internal combustion engine system is configured, in causing the cam switching device to perform a cam switching operation, to control the actuator such that the engagement pin is seated on a forward outer peripheral surface which is located more forward than an end of the cam groove on the forward side with respect to an insert section of the cam groove in the rotational direction of the camshaft.

An electronic control unit of a control device for an internal combustion engine executes, for a first cycle, first drive processing for controlling an actuator such that a pin drive operation is executed for switching from a first cam to a second cam, executes second drive processing for controlling the actuator such that the pin drive operation is executed again for a second cycle, and executes abnormality determination processing for determining that a cam switching mechanism has an abnormality in a case where a pin returns to a reference position by using a pin return section following a cam switching section of the first cycle after the execution of the first drive processing and the pin returns to the reference position by using the pin return section following the cam switching section of the second cycle after the execution of-the second drive processing.

A method of phasing the opening and closing of internal combustion engine intake and exhaust valves relative to the rotation of the crankshaft is based upon changes in engine speed, engine load and ambient relative humidity. During certain conditions of higher humidity, in order to maintain good combustion stability and thus overall engine operation, it is necessary to reduce intake and exhaust valve overlap by adjusting the phase of the intake and exhaust camshafts. This is achieved by utilizing a set of cam position reference values and constraints based upon engine speed, engine load and humidity that are contained in lookup tables that adjust and limit cam position and valve overlap. Generally speaking, in order to maintain optimum engine performance, intake and exhaust valve overlap is reduced with higher ambient humidity and vice versa.

Provided is a control device for an internal combustion engine equipped with a cam switching device including a cam groove provided on the outer peripheral surface of a camshaft and an electromagnetic solenoid type actuator capable of protruding, toward the camshaft, an engagement pin that is engageable with the cam groove. The control device is configured, in causing the cam switching device to perform a cam switching operation, to perform energization of the actuator such that the engagement pin is seated on a forward outer peripheral surface, and to more lower, when an electric current (coil current) flowing through the actuator as a result of the energization is greater, an average electric voltage per unit time applied to the actuator in protruding the engagement pin toward the cam groove from the forward outer peripheral surface.

An internal combustion engine system is provided with a cam switching device including a cam groove provided on the outer peripheral surface or a camshaft and an actuator capable of protruding, toward the camshaft, an engagement pin that is engageable with the cam groove. The internal combustion engine system is configured, in causing the cam switching device to perform a cam switching operation, to control the actuator such that the engagement pin is seated on a forward outer peripheral surface which is located more forward than an end of the cam groove on the forward side with respect to an insert section of the cam groove in the rotational direction of the camshaft.